DJControl Mix Ultra Jog Fix

Read this first. Firmware modification can void your warranty. Keep the backup file this page gives you. The controller's ROM update mode is the recovery path, so a bad application image can be restored. This site is independent and is not affiliated with Hercules or Guillemot.

Fix the controller

Put the controller in update mode

Power the controller off. Hold Neural Mix and power it on. Release the button when the computer shows STM32 BOOTLOADER.

Keep it connected by USB. Bluetooth cannot update the firmware. Use Chrome or Edge on desktop for the browser flash.

Connect and back up

This reads the current firmware and prepares a backup file. Save that file before applying anything.

Apply the fix

This erases the application area, writes the patched image, and reboots the controller. It takes about 20 to 40 seconds.

Power-cycle and verify

Unplug the USB cable, power the controller off, then power it on normally. Connect over USB MIDI and turn each ring slowly. Both rings should produce packets even at crawl speed.

Surface	Raw MIDI	Count
Left ring	`B1 09`	0
Right ring	`B2 09`	0
Left top	`B1 0A`	0
Right top	`B2 0A`	0

WebMIDI requires Chrome or Edge on desktop. This check is read-only.

What the fix changes

The stock firmware drops ring packets when the time between encoder edges is longer than two timer ticks. That is why slow pitch bends do nothing. The fix makes both ring paths send every valid edge, matching shift + ring.

Left ring becomes B1 09. Right ring becomes B2 09. The tops remain B1 0A and B2 0A.

Videos and Channel

Advanced: command-line fallback and recovery

If WebUSB is unavailable, use dfu-util on the command line. The browser flow above is the recommended path.

Back up

dfu-util -a 0 -s 0x08000000:0x40000 -U firmware_original.bin

Flash a patched image

dfu-util -a 0 -s 0x08000000:0x40000 -D firmware_patched.bin

Restore the backup

dfu-util -a 0 -s 0x08000000:0x40000 -D firmware_original.bin

Patch tool and technical notes: control-mix-ultra-jog-fix.